Catheter construction

ABSTRACT

Polymeric tubing, for use with catheters or other medical devices, where the polymeric tubing can have regions of customized properties including, but not limited to, durometer, torque control, flexibility, axial strength, stiffness, etc. One variation of the device allows for transitions between regions to be configured such that there can be gradual or customized transitions between various regions such that the structural characteristics differential between the regions selectively designed. Additional variations include outer layers having a plurality of material sections extending in a spiral direction along the axial length to form a continuous wall of the outer layer. In certain variations, the structural characteristic differential is minimized or eliminated as compared to conventional catheters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/173,003, filed Feb. 10, 2021, which is a divisional of U.S. patentapplication Ser. No. 16/902,154, filed Jun. 15, 2020, which is anon-provisional of U.S. provisional application No. 62/862,035, filed onJun. 15, 2019. This application is also related to PCT application no.PCT/US2020/037808 filed on Jun. 15, 2020, the entirety of each of whichare herein incorporated by reference.

FIELD OF THE INVENTION

Polymeric tubing, for use with catheters or other medical devices, wherethe polymeric tubing can have lengths of customized propertiesincluding, but not limited to, durometer, torque control, flexibility,axial strength, stiffness, etc. In one variation, the transition regionsbetween lengths can be configured such that there can be abrupt, gradualor customized transition regions between various lengths such that thestructural characteristics differential between the lengths and over thetransition regions are selectively designed. In certain variations, thestructural characteristic differential is minimized or eliminated ascompared to conventional catheters.

BACKGROUND OF THE INVENTION

Medical catheters allow physicians to apply a variety of differenttherapies within the body of a patient. Many catheters access remoteregions of the human body for delivering diagnostic or therapeutic toolsand/or agents to those sites. Alternatively, the catheter can comprise ashaft or support for a therapeutic working end (e.g., balloon, filterretriever, electrode, etc.). Some catheters, including but not limitedto catheters for neurovascular use, are intended to be advanced from amain artery (e.g., a femoral or radial artery) through tortuous anatomyinto a small cerebral vessel. As such, the catheter must be configuredwith varying structural traits due to the varying regions of the anatomythrough which the catheter passes. Many times, the vascular pathwayswind back upon themselves in a multi-looped path making it difficult forcatheter design to meet the requirements demanded by the tortuousanatomy. For example, catheters must be fairly stiff at their proximalend so to allow the pushing and manipulation of the catheter as itprogresses through the body, and yet must be sufficiently flexible atthe distal end to allow passage of the catheter tip through the loopsand smaller blood vessels. Regardless, the catheter not causesignificant trauma to the blood vessel or to the surrounding tissue/

FIG. 1A illustrates a traditional catheter construction and showssectional views of a catheter section 10 that can be constructed on aninner mandrel or core 12 that is later removed. The traditional catheterconstruction includes a layer 14 such as PTFE that provides a lubricioussurface for the interior of the catheter while also supporting variousstructural components to provide varying sections 16 and 18 of thecatheter 10. For example, the illustrated catheter 10 includes areinforced section 16 in which a braid or coil 20 (or both) are wrappedaround the second layer 14. Many catheters use metal braids in theproximal end of the catheter, and metal coils in the distal end of thecatheters (or one under the other). I

Many catheters intended to navigate through tortuous anatomy alsoinclude regions with varying durometer 18 in which polymers of differentdurometers 22, 24, and 26 are placed next to each other. FIG. 1A isintended for illustrative purposes to show basic structures ofconventional catheters. The catheter 10 of FIG. 1A, shows polymer 22terminates before a distal end 8 of the catheter 10 for illustrativepurposes to only show the underlying reinforced section 16. In mostconventional catheters, the entirety of the distal end is encapsulatedby a polymer.

As shown in FIG. 1A, various a series of adjacently placed polymerjackets 22, 24, 26 are placed over the reinforcement layer and fusedinto place (such as by heating and reflowing the polymer onto the braidor coil). Different polymer durometers (i.e. “stiffness”) are used fordifferent sections, as a result each of these sections of catheter willhave unique structural characteristics/properties, where the structuralproperties can include but is not limited to, stiffnesses, resistance totwisting or torsion, flexibility, column strength, etc. The illustratedconstruction 10 provides for varying structural characteristics over thevarying regions of the catheter. However, in conventional devices such acatheter construction yields abrupt changes in characteristics at thetransition or edge of each region 22, 24, 26.

In many conventional catheter devices, higher durometer polymers areused in the proximal region, with softer durometers placed as thecatheter progresses toward the distal end. More sophisticated cathetershave more “sections” or transitions of stiffness (i.e. more discreetpieces of extrusion of different durometers used for the outer jacket).For example, FIG. 1C shows a representation of an end of a Sofia® PlusDistal Access Catheter 19 manufactured by Microvention Termuo (AlisoViejo, Calif.), which is an example of a commercially availableintracranial catheter described by Microvention as having an“exceptionally soft distal tip” and “torqueable shaft” at the proximallength. The catheter includes an intermediate section 23 that isadjacent to a soft distal tip 25. The proximal length of the catheterisn't shown since FIG. 1C is intended to show that the intermediatelength 23 is constructed from a relatively higher durometer polymer andhas an abrupt transition to the relatively softer distal tip 25.Typically, a higher durometer polymer provides improved torque,rotational/axial stability but poor flexibility. As shown in FIG. 1C, apush force applied at the harder durometer polymer proximal end cancause the area 38 to buckle, which is approximately where the polymerschange. The buckling results in even worse push and navigation.

Typically, stiffer durometers are more suitable for the proximal regionof the catheter. Although stiffer durometer polymers do not bend as wellaround curves, they have greater positional stability in the vessels andtend to transmit torque well. In contrast, softer durometers aresuitable for the distal region of the catheter; because these polymersbend more easily and gently around the more delicate and tortuous distalcurves. However, softer durometer polymers do not transmit torque welland have poor positional stability. Thus, conventional catheter designsuse a “balancing act” between mechanical properties, where the designelements (stiff and stable, vs soft and less stable) are compromised.Additionally, the change from one durometer to another has long been asource of mechanical challenge. These transitions are a source ofdiscontinuity and are known in the field to cause challenges in torquetransmission and can lead to irregularities in bending stress whichleads to poor navigation in the anatomy. As such, engineers attempt tomake the transitions as long and gradual as possible, and to mitigateabrupt changes by having numerous small transitions as opposed to fewerlarger transitions.

Regardless of the length of the transitions, the traditionalconstruction as shown in FIG. 1A relies on the braid or coil 20 (orboth) used to transmit torque as the catheter navigates through tortuousanatomy. However, since the polymers 22, 24, 26 (etc.) are exterior tothe braid/coil 20, a greater degree of torque is applied to thepolymers. Polymers having different physical properties will also havedifferent resistance to torque. For example, in a variation wherepolymers 22, 24, and 26 have decreasing flexibility (22 being the mostflexible and 26 being the least), torque applied by the rotation ofsection 26 will not be fully applied to section 24. Therefore, section24 will not rotate as much as section 26. The same effect will occurwith section 22; its rotation will not be as much as section 24 and evenless than section 26. This results in poor torque control or torqueinstability. Furthermore, when these sections are flexed, the transitionbetween polymers creates discontinuities in how the catheter responds toflexing or bending across different sections.

FIG. 1B provides an illustration of a section of a catheter body 10(without abrupt transition regions) in a curved profile to represent thesection of the catheter body 10 being pushed to advance through tortuousanatomy. FIG. 1B illustrates a force 7 applied to a proximal end 9 ofthe catheter body 10, which is resisted by a wall of the vessel, whichis represented as force 6. In order to advance the catheter body 10,force 7 must be greater than force 6. When advanced through a tortuouspath, the catheter body 10 is placed in a state of tension 32 at anouter portion of the bend and a state of compression 34 in an innerportion of the bend. However, polymers are suited for either compressionor tension, and conventional catheter designs do not allow for selectionof a single polymer to maximize performance for both compression andtension. For example, polymers that respond well to tension at theoutside of the curve (e.g., generally softer polymers) might not respondwell to the compression at the inside of the curve. Likewise, polymersthat respond well to compression at the inside of the curve (e.g.,relatively stiffer polymers) do not respond well to the tension at theoutside of the curve. In addition, polymers must also be selected torespond to torsion and axial compression. Otherwise, problems with poortorque control or instability (e.g., referred to as “whip”) and axialinstability (commonly referred to as catheter backup) can result. As acompromise, traditional catheter design requires a balancing of polymerproperties but fail to produce devices that are optimized for any givenprocedure. Such a compromise results in undesired effects. For example,FIG. 1D provides an image of a React™ 071 catheter 36 supplied byMedtronic. The catheter 36 was held only at ends 37, allowing thecatheter to assume its naturally shaped profile. As shown, instead ofhaving a smooth bend radius or curve, the abrupt transition of thecatheter 36 causes the bend radius to be irregular at point 38, whichresults in buckling of the catheter when pushed. The buckling of thecatheter 36 reduces the transmission of the push force to the regionbeyond the buckling as well as decreased navigability.

The undesirability of abrupt transition regions is just one of thedrawbacks of traditional catheter design, which require a balancing actof compromising performance characteristics over any given sections of acatheter by selecting a less than desirable material. Accordingly, thereremains a need to improve catheter design and catheter structures toproduce a catheter with highly customized properties.

SUMMARY OF THE INVENTION

The catheters of the present invention allow for catheter constructioncustom designed without the need to compromise performance features.Such catheter constructions are possible by being able to customizeproperties and materials of any given section of the catheter. Suchcustomized properties include, but are not limited to, durometer, torquecontrol, flexibility, axial strength, stiffness, etc. The presentdisclosure also includes variations of improved catheters that havegradual or customized transition sections that can be configuredselectively. For example, any section of a polymeric tubing (andtherefore a finished catheter construction) can include polymers havinga low durometer, a moderate durometer, as well high durometer in thesame region. The ability to improve transitions is just one example ofthe benefit of an improved catheter constructed in accordance with theteachings herein.

For purposes of explaining the features of the present invention, thepolymeric strands/components represent the material sections describedherein prior to being formed into a tubular wall. As noted herein, insome variations, a material section can be formed from a first polymericmaterial and extend in a spiral pattern. At some point, the firstpolymeric material terminates at an end and is joined to an end of asecond polymeric material, which still extends or continues in thespiral pattern of the material section. In such a case, the materialsection is considered to have two different polymeric materials atdifferent lengthwise regions. In additional variations, a materialsection comprises a polymeric material and extends spirally for alengthwise region of the tubing then terminates such that adjacentmaterial sections join together to maintain continuity of the wall ofthe resulting tubing. It is also noted that, when referring to thejoined construction of individual strands, the term tubular wall,polymer tubing, polymer layer, composite tubing, composite layer, etc.can include material sections comprised of one or more materials: metal,stainless steel, alloy, liquid crystal polymer (LCP), fibers, compositematerial or other similar structures.

It is noted that a transition section shall be used to describe thechanging of one or more material strands with a different material. Theterm transition region shall describe the overall effect of the one ormore transition sections. In some variations, the transition region doesnot include any transition sections because a material simplyterminates. Therefore, catheter constructions of the present disclosurecan have a transition region that gradually changes material propertiesover an axial length or, alternatively, the transition region can be aregion of an abrupt change in material properties.

The present disclosure includes a number of variations of cathetershaving outer tubing layers formed form a plurality of materials tocustomize characteristics of the lengthwise regions of the catheters.Specific variations of catheters can also include this compositepolymeric layer as being on an interior layer of the catheterconstruction but in many variations, the custom composite layer is onthe outer layer.

Variations of such catheter tubing can include a tubular outer layerextending along an axial length of the tubular body; the tubular bodycomprising a plurality of material sections extending spirally along theaxial length to form a wall of the tubular body, where each materialsection is joined to an adjacent material section to form the wall;wherein the plurality of material sections include at least a firstmaterial section and a second material section, the first materialsection comprises a first structural property and the second materialsection comprises a second structural property, where the firststructural property differs from the second structural property; andwherein along a transition region of the tubular body a width of thefirst material section increases while a width of the second materialsection decreases causing a structural property of the transition regionto vary along the transition region.

Another variation of the catheter can include an outer tubular bodyhaving a first section and a second section each extending along anaxial length of the tubular body; wherein the outer tubular bodycomprises a plurality of material sections extending spirally along theaxial length, where each material section is sealingly joined to anadjacent material section to form a composite wall of the outer tubularbody which surrounds a lumen that extends along the axial length;wherein in the first section the plurality of material sections includeat least a first material section and a second material section formingthe composite wall, the first material section comprises a firststructural property and the second material section comprises a secondstructural property, where the first structural property differs fromthe second structural property; and a third material section having athird structural property, where the third material section is joined toan end of the first material section at the second section such thethird material section replaces the first material section in the secondsection.

An additional variation of the catheter includes a catheter tubingcomprising: a tubular body having a first section and a second sectioneach extending along an axial length of the tubular body; and aplurality of material sections extending spirally along the axial lengthto form the first section, where each material section is sealinglyjoined to an adjacent material section to form a composite wall of thetubular body that surrounds a lumen that extends along the axial length;wherein each of the plurality of material sections comprises astructural property respectively and where the structural property of atleast two material sections is different; wherein the first sectioncomprises a first sequence of material sections, and wherein the secondsection comprises a second sequence of material sections such that thematerial sections in the first sequence is different than the materialsections in the second sequence causing a structural property of thefirst section to be different than a structural property of the secondsection.

Another catheter construction includes a catheter constructioncomprising: a catheter shaft having an axial length, the catheter shaftcomprising a tubular outer layer comprising a plurality of materialsections each having a respective width measured along the axial length,the plurality of material sections extending in a spiral direction alongthe axial length to form a wall of the tubular outer layer, the tubularouter layer having a first lengthwise region, a second lengthwiseregion, and a transition region therebetween; wherein at the firstlengthwise region the plurality of materials sections includes a firstmaterial section and a second material section, where a structuralproperty of the first material section is different than a structuralproperty of the second material section to cause the first lengthwiseregion to have a first structural characteristic; wherein at thetransition region, the second material section terminates at an end anda third material section is joined to the end of the second materialsection, where the structural property of the second material section isdifferent than a structural property of the third material section; andwherein the first material section and the third material sectionspirally extend from the transition region to the second lengthwiseregion causing a structural characteristic of the second lengthwiseregion to be different than the structural characteristic of the firstlengthwise region.

Yet another variation of a catheter construction includes a cathetershaft having a tubular outer layer extending over at least a portion ofan axial length of the catheter construction, the tubular outer layercomprising a plurality of material sections each having a respectivewidth measured along the axial length, the plurality of materialsections extending in a spiral direction along the axial length to forma wall of the tubular outer layer, the tubular outer layer having afirst lengthwise region, a second lengthwise region; and wherein at thefirst lengthwise region the plurality of materials sections includes afirst material section at a first lengthwise region having a firststructural characteristic; wherein at the second lengthwise region atleast a portion of the first material section terminates at an end and asecond material section is joined to the end of the first materialsection, where the structural property of the first material section isdifferent than a structural property of the second material section tocause the second lengthwise region to have a second structuralcharacteristic different than the first structural characteristic.

Another variation of a catheter construction includes a tubular outerlayer comprising a plurality of material sections each having arespective width measured along the axial length, the plurality ofmaterial sections extending in a spiral direction along the axial lengthto form a continuous wall of the tubular outer layer; wherein theplurality of materials sections includes a first material section and asecond material section adjacent to the first material section, where astructural property of the first material section is different than astructural property of the second material section.

Another variation includes a catheter shaft having an axial length, thecatheter shaft comprising an inner liner, a reinforcement structureexterior to the inner liner, and a tubular outer layer extending overthe reinforcement structure; the tubular outer layer comprising aplurality of material sections each having a respective width measuredalong the axial length, the plurality of material sections extending ina spiral direction along the axial length to form a continuous wall ofthe tubular outer layer; wherein the plurality of materials sectionsincludes a first material section, a second material section, and athird material section, where a structural property of each of the firstmaterial section, second material section, and third material sectionare different; and the tubular outer layer having a first transitionregion where a width of at least one of the first material section,second material section, or third material section changes over thefirst transition region causing a change in a structural property of thefirst transition section.

Yet additional variations include medical tubing comprising: a tubularlayer comprising a plurality of material sections each having arespective width measured along the axial length, the plurality ofmaterial sections extending in a spiral direction along the axial lengthto form a continuous wall of the tubular outer layer; wherein theplurality of materials sections includes a first material section and asecond material section adjacent to the first material section, where astructural property of the first material section is different than astructural property of the second material section; and a firstlengthwise region of the tubular outer layer where a width of the firstmaterial and a width of the second material both change along the firstlengthwise region causing a structural property to change over the firstlengthwise region.

A medical tube can also include a tubular outer layer comprising aplurality of material sections each having a respective width measuredalong the axial length, the plurality of material sections extending ina spiral direction along the axial length to form a continuous wall ofthe tubular outer layer; wherein the plurality of materials sectionsincludes a first material section, a second material section, and athird material section, where a structural property of each of the firstmaterial section, second material section, and third material sectionare different; and the tubular outer layer having a first lengthwiseregion where a width of at least one of the first material section,second material section, or third material section changes over thefirst lengthwise region causing a change in a structural property of thefirst lengthwise section.

Another variation of a medical tube comprises: a catheter shaft havingan axial length, the catheter shaft comprising an inner liner, areinforcement structure exterior to the inner liner, and a tubular outerlayer extending over the reinforcement structure; the tubular outerlayer comprising a plurality of material sections each having arespective width measured along the axial length, the plurality ofmaterial sections extending in a spiral direction along the axial lengthto form a wall of the tubular outer layer, the tubular outer layerhaving a first lengthwise region, a second lengthwise region, and atransition region therebetween; wherein at the first lengthwise regionthe plurality of materials sections includes a first material sectionand a second material section, where a structural property of the firstmaterial section is different than a structural property of the secondmaterial section to cause the first lengthwise region to have a firststructural characteristic; wherein at the transition region, the secondmaterial section terminates at an end and a third material section isjoined to the end of the second material section, where the structuralproperty of the second material section is different than a structuralproperty of the third material section; and wherein the first materialsection and the third material section spirally extend from thetransition region to the second lengthwise region causing a structuralcharacteristic of the second lengthwise region to be different than thestructural characteristic of the first lengthwise region.

The present disclosure also includes one or more methods of forming apolymer tube. For example, such a method can include wrapping aplurality of polymer strands in a spiral configuration forming a polymertube, where at least two of the polymer strands comprise differentstructural properties; wherein in a first section of the polymer tubethe plurality of polymer strands forms a first sequence; altering thesequence of the polymer strands to form a second sequence in a secondsection of the polymer tube; and fusing each polymer strand to anadjacent polymer strand to form a continuous wall in the polymer tube,where the continuous wall defines a lumen therethrough and wherein astructural property of the first section differs from a structuralproperty of the second section due to the difference in the firstsequence and the second sequence.

Another catheter under the present disclosure includes an inner liner;an outer layer comprising a plurality of polymer strands wrapped in aspiral configuration, where at least two of the polymer strands comprisedifferent structural properties; wherein in a first section of the outerlayer the plurality of polymer strands forms a first sequence; where ina second section of the polymer tube the polymer strands form a secondsequence; and where each polymer strand is fused or joined to anadjacent polymer strand such that the plurality of polymer strands forma continuous wall defining a lumen through the polymer tube and whereina structural property of the first section differs from a structuralproperty of the second section due to the difference in the firstsequence and the second sequence.

Another variation of a catheter includes an inner liner; an outer layercomprising a first polymeric material having a tube shape, at least asecond polymer strand wrapped in a spiral configuration about the tubeshape and fused into the first polymeric material that at least aportion of the wall of the tube shape comprises the first polymericmaterial and the second polymeric material, where the first polymericmaterial and the second polymeric material comprise different structuralproperties; wherein in a first section of the outer layer the firstpolymeric material and the second polymeric material forms a firstpattern; wherein in a first section of the outer layer the firstpolymeric material and the second polymeric material forms a firstpattern; and where each polymer strand is fused or joined to an adjacentpolymer strand such that the plurality of polymer strands form acontinuous wall defining a lumen through the polymer tube and wherein astructural property of the first section differs from a structuralproperty of the second section due to the difference in the firstsequence and the second sequence.

The catheter and tubing configurations of the present disclosure allowfor a considerable number of combinations and permutations of differentvariations of catheters as well as combination of aspects of thosestructures as well. It is contemplated that any of the followingrequirements and elements can be combined with any independent claimwhere the requirements of the independent claims would not contradictthe various elements.

Any of the constructions herein can include the tubular outer layercomprising a plurality of material sections each having a respectivewidth measured along the axial length, the plurality of materialsections extending in a spiral direction along the axial length to forma continuous wall of the tubular outer layer.

Any variation of the devices/methods can further comprise an inner linerwithin the tubular outer layer and a reinforcement structure exterior tothe inner liner and within the tubular outer layer.

Variations can include the width of the first material section and thewidth of the second material section change along the first transitionregion.

Variations can include the tubular outer layer having a proximallengthwise region proximal to the first transition region, where theproximal lengthwise region is entirely formed from the first materialsection.

Variations can include a third material section extending over amajority of the axial length of the catheter tubular body.

Variations can include a width of the first material section beinggreater than the width of the second material in at least a firstsection of the wall of the tubular body.

Variations can include tapering of an end of the second materialsection.

The catheters and structures described herein can have material sectionsthat have a right-hand wind, a left-hand wind, or both.

Variations of any devices or methods herein can include at least one ofthe material sections comprises a non-fusable material. Moreover, such anon-fusable material can be used for manufacture only, whereupon removalof that non-fusable material imparts a groove cavity, or other designfeature on any surface of the device.

The devices herein can also include an inner liner within the tubularouter layer and a reinforcement structure exterior to the inner linerand within the tubular outer layer.

Variations of the device construction herein can further include atubular outer layer further having a second lengthwise region, a thirdlengthwise region, and a transition region therebetween; wherein thesecond lengthwise region includes the first material section and thesecond material section that define a structural characteristic of thesecond lengthwise region; wherein at the transition region, the secondmaterial section has an end and a third material section is joined tothe end of the second material section, where the structural property ofthe second material section is different than a structural property ofthe third material section; and wherein the first material section andthe third material section spirally extend from the transition region tothe third lengthwise region causing a structural characteristic of thethird lengthwise region to be different than the structuralcharacteristic of the second lengthwise region.

The catheter or catheter construction of any of the proceeding examplescan include an tubular outer layer that comprises a plurality ofmaterial sections each having a respective width measured along theaxial length, the plurality of material sections extending in a spiraldirection along the axial length to form a continuous wall of thetubular outer layer. Moreover, the changes in any material sections canbe incremental or continuously vary.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A illustrates a traditional catheter construction and showssectional views of a catheter section that is constructed on an innerextruded tube.

FIG. 1B provides an illustration of a catheter body in a curved profile.

FIG. 1C show a conventional catheter having multiple durometer regions.

FIG. 1D shows a representation of a photo of a catheter with havingabrupt changes in structural properties between regions and is held in abent or curved profile such that the abrupt change of the cathetercauses the bend radius to be irregular.

FIG. 2A shows a partial sectional view of an improved catheterincorporating an improved polymeric outer layer.

FIG. 2B illustrates a concept of a catheter shaft intended to illustratefeatures of the catheter design according to this disclosure.

FIG. 2C illustrates various paths through which variations of cathetersection of the present invention are specifically designed to navigatethrough.

FIG. 2D illustrates three catheters that have material sections that arewound in left-hand and right-hand directions.

FIG. 2E illustrates various cerebral vessels with a catheter that isadvanced through one of the carotid arteries.

FIG. 2F illustrates a conventional catheter when advance d through acarotid artery, where the conventional catheter includes differentsections having abrupt changes between sections.

FIGS. 2G and 2H illustrate a shape of an improved catheter when itadvances in the vessel of FIG. 2E and takes the shape of that vessel.

FIG. 2I illustrates one possible design configuration to produce acatheter construction using a composite tubing with material sectionscomprising different materials that each provide different mechanicaladvantages/benefits all within a single region of the finished catheter.

FIGS. 3A and 3B illustrate one example of the fabrication process toconstruct a catheter section under the present disclosure.

FIG. 3C illustrates a catheter section comprising a plurality ofdiscrete polymeric strands of material that are wrapped about a mandrelor tube.

FIG. 3D illustrates an image of an example of a wrapping process.

FIG. 3E illustrates a configuration where polymeric strands are securedtogether prior to being helically wound.

FIG. 3F illustrates three additional variations of polymer strandsarranged having varying properties.

FIGS. 3G and 3H show additional variations of polymer strands joinedtogether end-to-end and lengthwise prior to being helically wound andformed into a tubular body.

FIGS. 3I and 3J depict additional variations of non-uniform strandsjoined together prior to forming a tubing for use in a catheterconstruction.

FIG. 4A illustrates another variation of a group of joined strands priorto forming the tubular section depicted in FIG. 4B.

FIG. 4B illustrates a catheter section formed from the strands shown inFIG. 4A.

FIG. 5 shows a catheter section, which illustrates spacing ofdis-similar strands.

FIGS. 6A to 6C show variations of strands having reinforcing structures.

FIGS. 7A to 7F illustrate some examples of catheter sections formed fromvarious polymers.

FIGS. 8A and 8B shows a picture of a plurality of strands extending nextto a scale to illustrate a perspective of the strands for one variationof the catheter construction.

FIGS. 9A and 9B show two examples of sections of catheters having anouter layer that can be incorporated on a catheter or used as astand-alone device.

FIGS. 10A to 10D illustrate another variation of the device that changespolymers incrementally to construct a wound catheter with a graduallychanging transition region between different sections of the finishedpolymer tube.

FIG. 11A illustrates a graph of bend stiffness versus shaft location toaid in understanding the ability of catheters of the present disclosureto produce transition regions that are significantly improved over thecurrently available catheters.

FIG. 11B shows an image of a section of a catheter constructed inaccordance with the disclosure herein where the catheter section is heldin a position similar to the position of the catheter shown in FIG. 1C.

FIGS. 12A and 12F show images of various catheters to show variations ofpatterns that can be formed in joined polymer strands to producefeatures and/or patterns in a catheter section.

FIGS. 13A and 13B show a plurality of material sections havingadditional discrete materials formed therein.

FIGS. 14A to 14C illustrate another variation a composite polymer tubehaving a plurality of material sections where the material section isembedded within a polymer tube.

FIG. 15A illustrates a variation of a catheter having a hybrid-region.

FIG. 15B shows a magnified view of the vessels in region 15B of FIG.15A.

FIG. 15C illustrates a magnified view of the portion of the catheter inFIG. 15A that traverses an acute bend in arteries.

FIG. 15D shows a number of non-exhaustive design configurations toproduce a hybrid region as shown in FIGS. 15A and 15C.

DETAILED DESCRIPTION

The catheter configuration discussed herein can be used in a variety ofdevices where different regions are selected for customized properties.The configurations described herein can be incorporated into variousmedical devices or can be used as catheter shafts. Furthermore, in somevariations, the construction features of the present disclosure are notlimited to in-dwelling medical devices and can be used for any devicerequiring tubing.

The polymeric tubing described herein can be constructed in any mannerthat allows the material section configurations (and hybrid-regions)disclosed below. Such manufacturing means includes, but is not limitedto: forming the polymeric tube by winding directly onto catheter shaft;forming the strands into composite sheets and then winding the sheetonto a structure to complete a catheter shaft; and/or first windingribbons/strands onto a mandrel or support structure, then fusing thematerial into a tube, then transferring onto a catheter assembly.

FIG. 2A shows a partial sectional view of an improved catheter 100incorporating an improved composite outer layer 103 as discussed herein.The catheter construction discussed herein can incorporate any number offeatures known by those skilled in the art of catheter construction.Such features are omitted herein so that the focus of the improvedcatheter composite outer layer 103 can be explained. Furthermore, theimproved catheter construction disclosed herein can be incorporated intoany number of catheters that can benefit from a customization offeatures provided by the improved polymeric outer layer 103. Forexample, such catheters includes, but are not limited to, distal accesscatheters, sheaths, guide catheters, balloon catheters, intracranialsupport catheters, micro catheters, arterial line catheters, centralvenous catheters, pulmonary artery catheters, coronary and cardiaccatheters, and peripheral catheters etc.

Additional variations of the improved construction can be used in anypolymeric tubular structure. It should be noted that any catheterconstruction or polymer tubing disclosed herein is not limited to asingle uniform outer diameter across the entire catheter. As disclosedbelow, the catheters and polymer tubing of the present disclosure canhave an undulating outer diameter. Alternatively, or in combination, theouter diameter can vary throughout various lengthwise regions of thecatheter. The term lengthwise region is intended to mean a region of anylength along an axis 105 of the tube construction. The catheterconstructions and tubular constructions disclosed herein can have anynumber of conventional cross-sectional shapes. For example, variationsof the devices can include catheters that have different diametersand/or cross-sectional shapes at different regions. Some sections ofcatheters and tubular constructions can include round cross-sectionalshapes that change to non-round shapes.

As shown, in one variation of the device, the tubular construction orshaft of the catheter 100 extends from a hub 101 and can be formed bythe improved outer composite layer 103, discussed below, that overlays abraid 20, coil, or other support structure commonly used with catheters.The braid 20 is positioned about a tubular inner liner 14 (commonlyconstructed from PTFE but other materials are within the scope of thisdisclosure). As shown in FIG. 2A, the improved composite layer 103 isthe outermost component of the catheter tubing. As noted below, theimproved composite layer 103 can include any number of lengthwiseregions that are better suited to transmit torque through the catheter100. Positioning these polymeric torque transfer regions on the exteriorof the catheter improves the effectiveness of the torque transfer regionas compared to conventional catheters that mainly rely on the braid 20that is positioned within the catheter shaft.

FIG. 2B illustrates a concept of a catheter layer 103 intended toillustrate features of the catheter design according to this disclosure.The layer 103 can be incorporated into the catheter construction asshown in FIG. 2A or in any variation of such a construction (e.g., acatheter without a reinforcing structure 20 and/or a catheter without aliner 14). As shown, the catheter layer 103 can include any number ofregions 102, 104, 106, and 108, where the structural properties of eachregion can be customized based upon an intended purpose for the catheteror as otherwise needed. For example, the layer 103 illustrated in FIG.2B can be optimized or matched for use in a catheter that is intended tobe advanced through vasculature that has a varying tortuosity. In theillustrated example, referring to FIG. 2C, region 102 can be designed tonavigate tortuous region 52, while regions 104, 106, and 108 can bedesigned for respective regions 54, 56, and 58. FIG. 2B shows thecatheter layer 103 as having at least one material section extending ina spiral or helical pattern with a pitch that varies along the length ofthe finished layer 103. In one variation, the various lengthwise regions102, 104, 106, 108 can be matched to particular regions of thevasculature 52, 54, 56, 58 each having different levels of tortuosity.As described herein, the layer 103 can comprise any number of materialsections. Moreover, the actual material of any material section (e.g.,110, 112) can change over the length of the layer 103, which can resultin a new region.

FIG. 2B also illustrates that material section 110 comprises a helicalregion of a polymer extending adjacent to a second material section 112that comprises a second polymer (or alternate catheter material) tocreate regions (102, 104, 106, 108). having desired properties thatextends along the catheter 100. For example, a pitch of the firstmaterial section 110 can vary in each region 102, 104, 106, and 108.Alternatively, or in combination, a width of any of the materialsections can vary by region. For instance, the material section 110 cancomprise a reinforcing polymer (e.g., PEBAX 72D or similar material).

In another variation, the material section 110 can comprise a firstpolymer material (e.g., PEBAX 35D) within a second material section 112comprising a relatively stiffer material (e.g., PEBAX 40D-70D) where thehelical pitch of the material sections are selected such that a firstregion 102 is relatively firmer than the remaining regions, and where afirmness of an adjacent region 104 decreases relative to region 102.This varying of firmness can continue until region 108 is thesoftest/least stiff region and serves as a distal portion of thematerial layer 103, which in turn similarly affects the distal portionof a catheter incorporating the material layer 103.

The construction of the layers 103 of the present disclosure allow forany number of engineered catheters with custom properties. FIG. 2Dillustrates two layers 103 and 107 to illustrate that the novel layersof the present disclosure provide an ability to produce catheterconstructions having winding directions of either left-hand (layer 103)and right-hand (layer 107) winding of the material sections 110, 112 toproduce directionally biased catheters. having opposite winding featuresbetween distal 122 and proximal 124 regions. In the first variationshown in FIG. 2D, layer 103 can be used with a catheter that requiresvarying regions 102, 104, 106, 108. However, in this variation, region108 comprises a material section 110 having a loose pitch wound in aright-handed direction and comprising a stiff polymer strand to producea soft region that can be used to form a distal region of a catheter.The adjacent region 106 comprises a more moderate pitch of the materialsection 110 such that it is not as soft as region 108. The pitch of thematerial section 110 can increase in sections 104 and 102, which allowsfor increased support. While the figures in 2D only show two materialsections 110 and 112, any number of material sections formed frompolymeric material can be used to produce the varying sections of theouter layer 103 that forms the catheter. As noted above, the structuralcharacteristics of the various regions can be matched to thecharacteristics of the target anatomy. Moreover, the winding of thematerial sections 110 and/or 112 (or the specific material selection) asshown in either layer 103 or 107 can produce a specificdirectionally-wound catheter (i.e., a catheter that is pre-disposed tofollow a winding of a particular region of the anatomy). Specifically,the directionality of the winds can be matched to the directional twistof the vessels (i.e. left-hand wind catheter for left side internalcarotid artery and vessels, and right-hand wind catheter for rightinternal carotid artery and vessels, etc.). For example, a left carotidartery of an individual winds in a left-handed direction while a rightcarotid artery of that individual winds in a right-handed direction. Thecatheter constructions using the disclosed catheter layers (e.g., 103,107) produce a catheter that is suited to specifically follow the bendof a specific internal carotid artery or any other artery or bodypassageway. Generally, the direction of the reinforcement strand, asdiscussed herein, can pre-dispose the catheter to bend or navigate in aparticular rotational direction within the anatomy. As noted herein, thepresent disclosure permits customization of any region of a catheterconstruction with specific material characteristics. Moreover, catheterlayer 114 includes a single tubing having a right-handed windingadjacent to the distal end of the layer 114 and a left-handed windingadjacent to the proximal end of the layer 114. Clearly, the presentdisclosure includes winding of material sections in a single directionor multiple directions along the length of any tubing.

FIGS. 2E, 2G, and 2H further illustrate the benefit of the catheterusing the configurations disclosed herein. FIG. 2E illustrates variouscerebral vessels with a catheter 10 advanced through one of the carotidarteries 4, which is typically used to, access the brain. The carotidarteries 4 have various regions of tortuosity and decreases in diameteras the vessel advances further into the brain. FIG. 2F illustrates aconventional catheter that is advanced through the vessel 4 of FIG. 2Eand takes a shape of that vessel 4. This catheter 10 is similar to theconstruction shown in FIG. 1A, where the catheter includes varyingdiscrete regions of stiffness 21, 22, 24, 26, 27. As discussed above,although conventional catheters are designed to have different regions,each region has a discrete change in polymer (or other features such asremoval of an inner liner, alteration of a braid/coil structure, etc.)and therefore the catheter 10 has an abrupt change in structuralproperties at the intersection of each region 21, 22, 24, 26, 27. One ofthe issues with such designs is the loss of torque being evenly appliedacross the various sections. In other words, the torque 40 applied atthe proximal, stiffer section 27 will be greater than the torque 42 ofthe distal most section 21, which is generally the most flexiblesection. In addition to a difference in torque, the rotationaldeflection of the proximal section 27 will be greater than therotational deflection of the distal most section 21.

FIGS. 2G and 2H illustrate when an improved catheter 100 advances in thevessel 4 of FIG. 2E and takes the shape of that vessel. FIG. 2Gillustrates a variation of a catheter 100 of the present design but onlyshows a first material section 110 spirally wound with a second materialsection 112 for purposes of illustration. As noted herein and shown inFIG. 2H, any number of material sections can be used in a catheter 100.For purposes of illustration, the material section 110 comprises asingle polymer having a stiff material property (e.g., 72D). Thisexample shows the first material section 110 with the polymer thatextends the length of the catheter 100. Therefore, the helically formedpolymer strand material section 110 assists in transmitting applicationof torque 44 through length of the material section 110 along thecatheter 100 such that the torque 46 at the distal end is closer to thetorque 44 at the proximal end unlike conventional catheters.

FIG. 2H illustrates an additional variation of a catheter 100 having anumber of material sections 110, 130, 132, 134, 136, 138, 140, 142spirally extending along a length of the catheter 100. The materialsections shown in FIG. 2H are merely for the purpose of illustration,and any number of polymers can extend spirally about the catheter 100where some polymers cease or taper at different regions and differentpolymers begin such that various regions of the catheter can includedifferent polymers to give each region of the catheter a uniquestructural property. FIG. 2H is intended to illustrate the ability toposition a combination of materials along any section of the catheter100. For purposes of illustrating one variation of the catheter 100 amaterial section 110 of the catheter forms a majority of a wall of thematerial layer (see e.g., 103 in FIG. 2A) at the proximal end 122 of thecatheter 100. The polymer forming the material layer 110 at the proximalend 122 of the catheter 100 extends spirally along a length of thecatheter 110 and the material either changes or the material section isterminated prior adjacent to a distal end 124 of the catheter 100 suchthat the material sections at the distal end 124 comprise differentmaterial sections 130, 132 or different polymers. As noted herein, amaterial section can be terminated or a polymer in a material sectioncan be joined to an end of a different polymer in a material sectionsuch that the polymer changes in the same material section.

FIG. 2I illustrates one possible design configuration to produce acatheter construction using a composite tubing 103 with materialsections comprising different materials that each provide differentmechanical advantages/benefits all within a single region of thefinished catheter. The result is that the finished catheter section willachieve a mix of mechanical features within one region of the catheter.Such a configuration is simply not possible with conventional catheterdesigns. For example, FIG. 2I shows a composite layer or tube 103 havingmultiple material sections 280, 282, 284, 286, and 288. These materialsections can each provide unique benefits: material section 280comprises a low durometer ultra-soft material for high flexibility;material section 282 comprises a moderate durometer material thatprovides some flexibility as well as axial stability; material section284 comprises a high durometer material that provides enhanced torquecontrol as well as rotational and axial stability. Material sections 286and 288 are shown to represent that the composite tube 103 can includeany number of additional material layers.

The various polymer strands used to fabricate the catheter (or outerlayer) can be selected to impart desired characteristics for thecatheter 100 based upon a desired use of the catheter and/or dependingon the intended path of the target within the body. This constructionallows various characteristics of any polymer to be extended acrosssections of the catheter 100 or an entirety of the catheter 100 suchthat the catheter does not contain any regions of abrupt changes instructural characteristics/properties that affect bending, torqueing,flexing, etc. rotational stability and axial stability

FIGS. 3A and 3B illustrate an example of the fabrication process toconstruct a catheter section under the present disclosure. It iscontemplated that any manufacturing process that creates a catheter orcatheter layer with a plurality of material sections is within the scopeof this disclosure. For example, such manufacturing processes caninclude wrapping polymer strands (as shown), 3D printing, extrusion,etc.). As shown in FIG. 3A a number of polymer strands or ribbons areplaced in a pattern to coincide with material sections 130, 132, 134,136 and can be wrapped about a structure 116. The structure can comprisea mandrel, tube, or a braid/liner of a catheter structure. Once thepolymeric strands are wrapped, they are fused or otherwise joinedtogether to form a layer as described here (e.g., see layer 103 of FIG.2A). In one variation, the wrapped and joined polymer ribbons form awall layer of a catheter after they are fused together. Alternatively,the polymer ribbons can form an outer layer over a tube, braid and/orcoil 116 and form a portion of a catheter section. For sake ofconvenience, the polymer strands/ribbons/extrusions shall be referred toas polymer strands. The present invention includes the polymer sectionsas having any shape necessary to complete the catheter section. Asshown, a cross section of the polymer strands can be rectangular.Alternatively, the polymer strands can be oval, round, or have any othershape. In additional variations, polymer strands of different shapes andsizes can be combined to form a layer. Moreover, the polymer strands cancomprise single lumen extrusions/tubes that are collapsed andmelted/fused down. Alternatively, the strands can be extruded orotherwise manufactured to be solid. In another variation, the lumen ofeach polymeric strand is left intact. In a typical variation, thestrands are wound over a braid or coil (as discussed above). In anadditional variation, the polymer strand construction discussed hereincan be used to form an inner layer of a catheter (instead of or inaddition to a polymeric liner), with a separate construction being usedfor an external layer of the catheter. In an additional variation, eventhough the disclosure herein discusses strands and material sections ascomprising polymers. A strand or material section can comprise anon-polymeric material (e.g., metal, stainless steel, alloy, liquidcrystal polymer (LCP), fibers, composite material or other similarstructures). Strands can be different materials, shapes, sizes, andmixed together, or can be placed and removed to leave voids. Strands canalso be different materials, shapes, sizes, and mixed together, or canbe placed and removed to leave voids.

For purposes of explaining the features of the present invention, thepolymeric strands/components represent the material sections describedherein prior to being formed into a tubular wall. As noted herein, insome variations, a material section can be formed from a first polymericmaterial and extend in a spiral pattern. At some point, the firstpolymeric material terminates at an end and is joined to an end of asecond polymeric material, which still extends or continues in thespiral pattern of the material section. In such a case, the materialsection is considered to have two different polymeric materials atdifferent lengthwise regions. In additional variations, a materialsection comprises a polymeric material and extends spirally for alengthwise region of the tubing then terminates such that adjacentmaterial sections join together to maintain continuity of the wall ofthe resulting tubing.

Regardless of the fabrication process, the polymer strands in each ofthe material sections 130-136 can comprise polymers of varyingcompositions. In one example, the polymers can be a common material(e.g., PEBAX) where each strand in a respective material section 130-136comprises a different durometer. For example, the strands can have thefollowing associated durometers: 130—72D, 132—63D, 134—35D, and 136—45D.Clearly, any number of variations are within the scope of thisdisclosure.

FIG. 3A also illustrates the plurality of material sections 130, 132,134, 136 each having a respective width W1, W2, W3, and W4, measuredalong an axial length 105 of the tube. In this illustration, the axiallength 105 is the axial length of the core or tube, which will generallybe similar if not the same as an axial length of the finished tube or acatheter having a layer formed by material sections 130, 132, 134, 136.In the case of materials not yet formed into a tube structure, the widthis measured in a plane that is perpendicular to a length of the strand.As shown in FIG. 3B the material sections extend in a spiral directionalong the axial length 105 to form a continuous wall as discussedherein.

FIG. 3C illustrates a wall section 103 after a plurality of discretepolymeric strands of material in material sections 130, 134, 132, 136are joined together a support structure 116. The section 103 can beincorporated into a medical catheter, medical device, and/or othertubing.

FIG. 3D illustrates an image of an example of a wrapping process wherestrands of polymer form material sections 138, 140, 142 and are wrappeddirectly onto a catheter reinforcement braid 116. (alternative, thestrands could be wrapped onto a mandrel, fused or partially fusedtogether, and then transferred onto the catheter braid as conventionalcatheter construction). In this variation, the strands 138-142 areseparate and are wrapped such that the strands are in contact forfusing.

FIG. 3E illustrates a configuration where polymeric strands 130-134 thatare secured together prior to being helically wound to form materialsections 130-134. For example, the strands can be fused together ortacked together prior to winding.

FIG. 3F illustrates three additional variations of polymer strandsarranged having varying properties. In the illustrated example, thedurometer of the strand is shown. However, the polymer strands can varyother properties as needed. As shown in the bottom-two variations, twostrands of a similar configuration can be placed adjacent to adis-similar strand. When formed into a tubular member the centermaterial section will be bounded by material sections having the samepolymer.

FIGS. 3G and 3H show additional variations of polymer strands 130, 132,134, 130-134 joined together end-to-end and lengthwise prior to beingformed into a wall where strands 134 will ultimately form the materialsections on either side of the material section formed by strands 130and 132. In this variation, strands 130 and 132 are joined end-to-end ata transition section 120 to allow for a transition of materialslengthwise along an axial direction of the finished catheter. This meansthat when formed into the tubular member/wall the center materialsection comprises material 130 joined to material 132 at edge 120. Thejoint or transition section 120 between strands 130 and 132 can be anabrupt transition section 120 as shown in FIG. 3G or an angled ortapered transition section 120 as shown in FIG. 3H.

FIGS. 3I and 3J depict additional, but not exhaustive, variations ofstrands 130, 132, 134, 136 being joined together where the strands arenot uniform. For example, FIG. 3I illustrates a strand 134 as having acircular cross-sectional shape. As noted above, any type ofcross-sectional shape can be used. In such cases, a width W3 of thestrand 134 can be considered its widest dimension along the axis. Insome variations, the size of the strand 134 will cause the resultingmaterial section to slightly protrude from a surface of the tube. FIG.3J illustrates such a case, where a height H1 of certain strands 134 arejoined with a strand 132 having a greater height H2. FIG. 3J alsoillustrates the widths W5 and W6 of the strands as not being uniform.Again, any permutation of shapes, sizes, widths, heights, etc. can becombined to make a polymer layer. It should be noted that any strand ofmaterial incorporated into a composite polymeric layer can includestrands of material having a melt temperature different than one or moreadjacent strands. It is also noted that in some variations, one or morestrands can be non-meltable (i.e., a thermoset material, or metals,Teflon, etc.) that are mechanically held by the adjacent strands but donot melt. In additional variations, the non-meltable strand is usedduring formation of the tubing and then removed to create a void orpattern.

FIG. 4A illustrates another variation of a group of joined strands130-138 prior to forming the tubular section depicted in FIG. 4B. Asshown, the strands comprise different properties resulting differentsection 102, 106, and 108 for the catheter. When wound, as shown in FIG.4B, the varying of the composition of material sections 130-138 formdifferent axial sections 102, 106, 108 extending lengthwise along thetubular layer 103. In both variations depicted in FIG. 4A and FIG. 4B,the strands/tubular layer 103 include a single strand 130 that willextend continuously as a material section 130 over a full length of thefinished tube 103. In this example, the strand 130 comprises a 72Dmaterial and is can be ultimately used as reinforcement for the finishedcatheter. (mainly used to transmit torque and provide stability througha normally soft and flexible distal region that usually does nottransmit torque well and usually has poor stability).

FIG. 5 shows a section 102 of a tubing where strands 152 and 154 arejoined to form the tube. The figure illustrates spacing of dis-similarstrands 152 and 154. In the example, strands 152 can be separated by asecond 154, where this second strand either comprises segments havingthe same width as strand 152 or the second strand 154 has a greaterwidth than the first strand 152. As noted above, the width is measuredalong an axial length of the tube. For example, strand 152 can comprisea high durometer material while strand 154 comprises a relatively lowerdurometer material. In an alternate variation, strand 152 comprises alow durometer material while strand 154 comprises a high durometermaterial. For example, in one variation of the device a low durometermaterial could range between 35D to 45D while a high durometer materialcan range between 63D and 72D. Clearly, additional variations ofmaterial are within the scope of this disclosure.

FIG. 6A illustrates an additional variation of a catheter constructiondescribed herein where a polymer strand 130 includes a support member156 extending therethrough that reinforces the strand 130 or providesalternate structural and characteristics. The support member 156 canextend through a full length of the strand 130 or partially through astrand. Moreover, a variation of the reinforced strand 130 can include aplurality of support members that extend through a strand. FIG. 6Billustrates a cross-sectional view of a strand 130 to illustrate somecross-sectional shapes of reinforcement members. As shown, thereinforcement member can have circular 158 or elliptical cross section,the support member can have a rectangular or square 160 cross section,or the support member can comprise a D-shaped 162 cross section. Thesupport member can comprise a metal, an alloy, or polymer. For example,the support member can comprise SS wire, a shape memory wire, a drawnfilled tube, or a composite fiber material. It can be in a cable, braid,coil, strand, etc. or any shape/structure/material used to providesupport. FIG. 6C illustrates various complex cross-sectional shapes 164for a support member within a strand 130. In certain variations, thecatheter section can comprise different cross-sectional shapes indifferent sections of the catheter. For example, it was found thatstrands with a circular or oval cross-sectional shape are better suitedfor a distal region of a catheter while, strands with a D-shaped supportmember are useful at the mid or proximal region of the catheter.

FIGS. 7A to 7F illustrate some examples of tubular sections 203 formedfrom various polymers to have multiple material sections extending in aspiral pattern along the tubing 203. For purposes of illustration in 7Ato 7F, the materials properties are shown in association with thefollowing element numbering: 35D —235, 45D —245, 55D —255, 63D —263, 72D—272. However, this association is intended to demonstrate variations oftubing 203. Any variation of materials can be used in the catheterconstructions described herein. Furthermore, any tubing section 203 canbe used in any segment of a completed catheter as discussed herein. Theillustrations of FIGS. 7A to 7F are intended to show a non-exhaustivecombination of segments. In each figure, the pattern illustrated by therespective material sections 235, 245, 255, 263, 272 repeats to providethat segment of the tubing 203 with unique properties. For example, FIG.7B illustrates a pattern where a 55D material section 255 is immediatelybetween two 45D material sections 245 and that assembly is between two35 D material sections 235. This configuration can providecharacteristics that allow for a “shock absorber” effect. In FIGS. 7C,7D, 7E, and 7F certain strands are doubled during construction of thetubing 203 to provide for wider material sections with thatconfiguration. For example, the material section 235 in FIG. 7D is shownto be nearly twice the width of material sections 245, 255, and 263.FIG. 7E shows material section 255 as nearly twice the width of sections263 and 270. FIG. 7F shows material sections 245 and 255 as being nearlytwice the width of section 263. Again, the illustrated variations areintended to provide a non-exhaustive sample of variations for possiblecatheter construction.

FIGS. 8A and 8B shows an example of strands 130 and 132 extending nextto a scale 30 to illustrate a perspective of one example of strands 130and 132 that ultimately form a tubular member as described above wherethe overlap or staggering of the polymer end-joint locations, produces afinished polymer tube/catheter construction with a transition region 129that is significantly improved over conventional catheter constructions.FIGS. 8A and 8B demonstrate how the overlap or staggering of thepolymers at individual transition sections 120 (where the materials eachhave a butt-joint location) such that the end of 130 adjoins the end of134), and will, when wrapped, result in a significantly improvedtransition region 120 over the conventional catheters discussed above.As shown, the configuration of FIG. 8A includes staggered transitionsections 120, which creates a transition region 129 similar to thatshown FIG. 9A. As noted herein, when strands 130 and 132 are formed intoa tubular member, the strands 130 collectively form a material sectionthat changes from a first material over region 129 to a second materialhaving the material of strands 132. FIG. 8B shows a variation similar tothe example of FIG. 8A with strands 134 joined/spliced end-to-end withstrands 130. However, strand 136 remains continuous. When fabricatedinto a tubular member, strands 134 form a material section that changesin materials as described with respect to FIG. 8A, but the tube sectionformed by FIG. 8B includes a material section formed by strand 136 thatremains constant.

FIGS. 9A and 9B show two examples of sections of catheters having anouter layer 103 that can be incorporated on a catheter or used as astand-alone device/structure. FIG. 9A illustrates a material section 130formed from a first polymer and a material section 132 formed from asecond polymer. The outer layer 103 includes a lengthwise region 129 ofthe tubular layer where a width of the first material section 130 and awidth of the second material section 129 both change in width along thelengthwise region 129 causing a structural property to change over thefirst lengthwise region 129. As shown, the right side of FIG. 9Acomprises a tubular member where an entirety is formed from materialsection 130 and a left side where an entirety of the material section132 is formed from material section 132. In the transition region 129,the widths of the respective material sections inversely change alongthe lengthwise region 129 such that as the width of the first material130 decrease towards the left and the width of the second materialsection increases. These transition regions can be made as long andgradual as desired, by adjusting the length of section 129, and byadjusting the number of strands/ribbons used, to give drasticallyimproved and superior transition regions compared to conventionalcatheters.

FIG. 9B illustrates a variation of a tubing 103 having a plurality ofmaterial sections 130, 132, 136 spirally wound to form the tubing 103where the tubing 103 includes a joint 120 where material section 130changes to a different material 134, that continues in the spiralpattern of material 130. This end-to-end joining of materials allows thematerial section to continue while changing materials.

FIGS. 10A to 10D illustrate another example of an arrangement of strandsto form a tubular member for use in a catheter. FIGS. 10A and 10C show agroup of joined strands that can be varied to produce configurations asshown in 10B and 10D respectively. FIG. 10A illustrates a 5-strandconstruction, where one end of the joined strands comprise strands 204of a first polymer. The strands 204 of the first polymer are eachreplaced at individual transition sections 120 that are staggered togradually replace strands 204 with strands 206 of a second polymer overa transition region comprising length 172, 174, 176, and 178. Thisconstruction allows for a gradual variation over the transition region172, 174, 176, 178 along the finished tubular assembly 103 (as shown inFIG. 10B) that has the properties of the first polymer in a firstlengthwise region 170 and gradually changes over transition region 172,174, 176, and 178 to the properties of the second polymer untillengthwise region 180 comprises all of the second polymer. Thetransitioning of materials in lengthwise regions 172, 174, 176, 178represents an example of gradually transitioning material propertiesover a lengthwise transition region of a tubular assembly 103 orfinished catheter construction. Clearly, any number of material sectionsor widths of material sections can be used to increase or decrease therate of transitioning material properties. Moreover, variations of thedevices described herein do not require staggering of transitionsections 120. While staggering is usually desired to obtain a gradualtransition, the transition regions can comprise an abrupt change inmaterials when desired.

It is noted that a transition section shall be used to describe thechanging of one or more material strands with a different material. Theterm transition region shall describe the overall effect of the one ormore transition sections. In some variations, the transition region doesnot include any transition sections because a material simplyterminates. Therefore, catheter constructions of the present disclosurecan have a transition region that gradually changes material propertiesover an axial length or, alternatively, the transition region can be aregion of an abrupt change in material properties.

FIG. 10B also illustrates that each lengthwise region 172, 174, 176, 178comprises at least two material sections 204 and 206 where a width of amaterial section 204 or 206 increases or decreases while the othermaterial section 206 or 204 decreases or increases respectively. Thevariation of the tube 103 shown in FIG. 10B also includes lengthwiseregions 170 and 180 entirely formed a single material section. Again,any tube construction 103 discussed herein can be incorporated into acatheter construction as shown in FIG. 2A, or such tube construction 103can be incorporated into any medical device or non-medical device.

As shown, the catheter section can comprise the various sections:section 170 consists of 5 strands of a first polymer (5 and 0); section172 consists of 4 strands of the first polymer and 1 strand of thesecond polymer (4 and 1); section 174 comprises 3 strands of the firstpolymer and 2 strands of the second polymer (3 and 2); section 176comprises 2 strands of the first polymer and 3 strands of the secondpolymer (2 and 3); section 178 comprises 1 strand of the first polymerand 4 strands of the second polymer (1 and 4); and section 180 comprises5 strands of the second polymer (0 and 5). The construction of FIG. 10Aproduces the catheter shown in FIG. 10B after the strands are helicallyformed and melted into a catheter section.

FIG. 10C illustrates a plurality of joined strands where section 190comprises 4 strands 208 of a first polymer and a single strand 210 of asecond polymer (4 and 1). As shown, in the change to region 192 onestrand 208 is tapered leaving only four strands (3 and 1). The nextsection 194 another strand 208 is tapered leaving only 3 strands (2 and1). The process continues through sections 196 (1 and 1), until thestrand 210 of the second polymer remains. The wrapping of the joinedstrands is adjusted (e.g., the pitch is altered) such that the reductionin number of strands does not leave any openings or gaps betweenstrands. This construction produces a tube construction 103 similar toFIG. 10D As shown, the tubular construction 103 includes two materialsections in lengthwise region 109, the width of the material section 210increases in section 192 relative to section 190 while the width ofmaterial section 208 decreases in section 192 relative to section 190.The widths of material sections 208 and 210 continue to inversely changethrough lengthwise regions 194 and 196 until region 198 includes asingle material section 210. The construction shown in FIG. 10D shows atubular section 103 having transition regions 192, 294, 196 where thematerial sections change but there are no transition sections ofmaterials 208 since the material just terminates as shown in FIG. 10C.While the construction of FIGS. 10A/10B and 10C/10D are different, bothdesigns produce a shaft that transition from a first material propertyto a second material property using a very gradual basis. Thisgraduation and uniformity is significantly greater than what can beproduced with conventional catheter technology. On example of thematerial properties is stiffness/softness. For example, the catheters of10B and 10D can transition from a relatively stiff material property ate.g., 170 of FIG. 10C and 190 of FIG. 10D to a much softer materialproperty at e.g., 180 of FIG. 10B and 198 of FIG. 10D. The transitionregion (e.g., 172-178 FIG. 10B and 192-196 of 10D) can be customized byselection of polymers, length of transitions, etc. to producetransitions that were simply not found in currently available commercialcatheters. It is also noted that the lengths of regions 170-180 and190-198 (as well as the lengths throughout this disclosure) are intendedto convey the principles of the present designs. The lengths are notrequired to be the same and are not to scale unless otherwise claimed.

Clearly, the length of each section shown in FIGS. 10A and 10C isintended for illustrative purposes only. In addition, any number ofpolymer strands can be used along with any number of polymers. Moreover,it is noted that in FIG. 10A, a material section can be considered allof the separate elements 204 of the same material. Therefore, region 170includes a material section that changes in width stepwise to region 172and so forth. The change in width can be stepwise or incremental asshown. Alternatively, the change can be tapered such that the change inwidth is continuous as shown by regions in FIG. 10C where the ends ofmaterial 208 taper off.

FIG. 11A illustrates a graph of bend stiffness versus shaft location toaid in understanding the ability of catheters of the present disclosureto produce transitions regions that are significantly improved over thecurrently available catheters. FIG. 11A illustrates the result of a testwhere a force is measured to displace a catheter by a given distance,commonly known as a 3-point bend test. The catheter is supported at twopoints such that a gap between the two points will be deflect by thegiven distance. The force required to produce this deflection ismeasured and graphed to correspond to a distance from the distal end ofthe catheter. For example, the left side of the graph shows the amountof force required to displace the catheter section at the closest pointto the distal end of the catheter (i.e., the distal end). The right sideof the graph of force shows the amount of force required to displace thecatheter section at the closest point to the proximal end of thecatheter. The three catheters tested in this manner included a catheter300 constructed under the present disclosure, a commercially availablecatheter 302 manufactured by Medtronic (React 071), and a commerciallyavailable catheter 304 manufactured by Penumbra (ACE 068). The graphshows the improved catheter 300 as having a gradual increase in bendstiffness with no sudden or irregular increases in bend stiffness. Incontrast, the graphed data of the Medtronic catheter 302 bend stiffnessshows two significant regions of abrupt changes in properties 306. Thegraphed data of the Penumbra catheter 304 bend stiffness shows threesignificant regions of abrupt changes 306.

FIG. 11B represents a section of a catheter constructed in accordancewith the disclosure herein where the catheter section is held in aposition similar to a position of the catheter shown in FIG. 1D.However, the improved catheter 310 is constructed in accordance with thedisclosure such that materials are actively selected to provide desiredproperties and characteristics of the catheter 310 over variouslengthwise regions 312, 314, 316, and 318 to avoid any areas of abruptchanges that would otherwise cause bending irregularities. FIG. 11Bshows just one example of a catheter 310 using materials 134, 206, 208,and 210. Clearly, any number of combinations, as described herein, arewithin the scope of this disclosure. As shown, lengthwise region 312includes three material section of materials 134, 206 and 210.Lengthwise region 314 includes two materials sections of materials 206and 210. Lengthwise section 316 includes three material sections ofmaterials 206, 208, and 210. This section also shows material sectionschanging in width such that a thickness of material/material section 206decreases and material/material section 208 increases in a directiontowards lengthwise section 318. Lengthwise section 318 includes twomaterial sections of materials 208 and 210. The end result of theconstruction of catheter 310 is that lengthwise sections 312 and 314comprise significantly different structural characteristics as comparedto lengthwise section 318 but the change is sufficiently gradual toavoid significant discontinuities in bending stiffness.

FIGS. 12A to 12D are greyscale images of exemplary catheterconstructions under the present disclosure. FIG. 12A illustrates 3different catheter sections 320, 322, and 324 each having differenthelical pitch angles (i.e., the angle the material section 134, 132makes with an axis of the catheter). Catheter 320 shows a near radialangle (meaning the angle is almost perpendicular to the axis). Theconstruction for this catheter section included two strands: one strandof material 134 and one strand of material 132. Catheter 322 shows anintermediate pitch angle. The construction for this catheter sectionincluded 4 strands: one strand of material 134, one strand of material132, one strand of material 134 and one strand of material 132. Catheter324 shows an increased pitch angle relative to catheters 320 or 322. Theconstruction for this catheter section included 6 strands: one strand ofmaterial 134 and one strand of material 132 repeated three times. Thegreater number of strands used during construction allow for a greaterincrease in pitch angle.

FIG. 12B shows another greyscale image of another variation of aconstructed catheter section having two material sections of the samematerial on either side of a material section having a flexible material134 with a material section 130 having a larger width. Such aconfiguration can comprise a “shock-absorber” if materials 132 arestiffer materials. FIGS. 12C and 12D show catheters constructedaccording to the present invention with undulating outer surfaces. FIG.12C shows a greyscale image of another example of a constructed cathetersection similar made in a similar manner as the construction shown inFIG. 3J. In this variation, a height of material 132 was greater than aheight of the adjacent material 134 and a width of material 132 is lessthan adjacent material 134. In spite of the height differences, thematerials were able to be fused together to form the polymer layer. FIG.12D illustrates another catheter where material section 134 has adiameter that is greater than adjacent materials 132, and 130. Inanother variation, the undulating surfaces can be formed using one ormore materials during the fusing process (e.g., as described in FIG. 3A)with a non-fusable material (e.g., a high melt-temperature polymer suchas PTFE, a metal alloy, etc.) on top of the strands such that thenon-fusable material is removed to leave a void in the finished polymerlayer.

FIGS. 12E and 12F shows pictures of variations of tubing 330-348 thatcan be incorporated into a catheter or used as a tube device without acatheter construction. FIGS. 12E and 12F show two material sections 230,232 that can comprise any variation of materials. In one example, FIG.12E shows section 230 comprised of a hard 72D durometer ribbon (used asa torque coil) imbedded within section 232 comprising a softer 60Adurometer ribbon. The pitch (i.e. spacing) of material 230 increasesfrom 330 to 340, by increasing the number of material sections in eachunit. I.e. tubing 330 has a single material section 230 with materialsection 232. In contrast, construction 340 was formed from aconstruction that included multiple strands of material 230 and multiplestrands of material 232.

FIG. 12F shows a picture four tubings 342, 344, 346, and 348 where anangle of material section 230 and material section 232 varies in eachtube. In each of these units, the spacing (i.e. pitch) of materialsection 230 white 72D coil does not change (i.e. width of materialsections 232 in between material section 230 is the same dimension ineach of the units). However, the angle of the material section 230changes in each unit. For example, tube 342 shows an angle of materialsection 230 that is the most radial (i.e., extending in a radialdirection from the tube), while the bottom tube 348 comprises the mostaxial or linear material section 230. Tube 342 comprised three strands:one strand 230 and two strands 232 to produce material section 230 and232. Tube 344 was constructed with 6 strands: 230×1+232×2+230×1+232×2.Tube 346 was constructed from nine strands and tube 346 was constructedfrom 12 strands using the same arrangement.

FIGS. 13A and 13B depicts another feature of the catheter constructionwhere a plurality of strands (either a similar polymer or differentpolymers) is joined together as discussed above. However, in thesevariations, a variety of discrete materials (i.e., polymers, metals,composites, alloys, etc.) can be patterned on the joined strands 130. InFIG. 11A a polymer is patterned into the illustrated shape 214. The basestrands 130 can be removed or the polymer 214 can be positioned on topof the base strands. Likewise, multiple polymers 214 and 216 can bepositioned on a base strand 130 of polymers. In alternate variations,the base polymer strands 130 can be removed such that the patternedpolymer 214 or 216 can be positioned in the space left by the removedbase strand 130. The finished assembly 130 can be fabricated into a tubeconstruction for incorporation as a catheter or other medical deviceshaft.

FIGS. 14A to 14C illustrate another variation of constructing acomposite polymer tube 294 having a plurality of material sections underthe present disclosure. As shown in FIG. 14A, the initial constructioncan comprise a conventional polymer tube 290 with one or more strands292 wrapped about the tube 290. The tube 290 and strand 292 are thenheat fused together to produce a composite polymer layer 294 where thestrand 292 becomes at least partially embedded within the tube 290 suchthat the polymer layer 294 comprises a first material section comprisingmaterial 290 of the tube and a second material section comprising 292 ofthe strand. Clearly any number of variations of strands (as describedabove) can be embedded within the tube. Moreover, the outer diameter ofthe polymer layer 294 can include undulations. FIG. 14C illustrates thepolymer tube 294 with a portion removed to highlight the cross-sectionalarea of the polymer layer. In an additional variation, the constructionof FIGS. 14A to 14C can replace the conventional polymer tube 290 with acomposite polymer tube with varying material sections constructed asdescribed herein.

FIG. 15A illustrates a partial view of a patient's anatomy todemonstrate one feature of catheters 100 of the current disclosure. FIG.15A illustrates the catheter 100 being inserted using a radial accessprocedure. Clearly, the catheter constructions described herein (as wellas the polymer layers) can be incorporated in any device where selectionof materials for specific performance characteristics is desired. Radialaccess procedures are becoming more of a desirable access point forinterventional procedures. Radial access is the dominant mode forcardiac procedures and is becoming more commonplace for neurovascularprocedures. However, the acute bends, particularly in trying to accessthe neurovascular, create considerable challenges for conventionalcatheters. The catheter constructions described herein are well suitedto address the acute anatomical challenges faced by conventionalcatheters.

FIG. 15A illustrates a catheter 100 of the present disclosure advancedinto a radial artery 50 and navigated to a right subclavian artery 51,and into an internal carotid artery 53 and ultimately to a neurovascularvessel 60. The catheter 100 shown in FIG. 15A includes regions ofvarying material sections as discussed above. However, this variation ofthe catheter 100 includes a hybrid-region 220 that allows for multiplecatheter performance characteristics at the region. Such a configurationnot only allows for navigation through a tortuous bend but also does notsuffer from the same drawbacks as a catheter simply constructed from asoft polymer. The present disclosures contemplate catheters having anynumber of hybrid-regions with any permutation of materialcharacteristics.

FIG. 15B illustrates the area from FIG. 15A and shows an acute bendbetween the right subclavian artery 51 and the right internal carotidartery 53. The catheter is removed from FIG. 15B for the purposes ofillustrating the bend. Conventional catheters encounter problems whenadvanced through such acute bends because it is difficult forharder/firmer polymers to navigate through tortuous curving of theanatomy. Softer polymers are able to navigate such acute bends, but thesofter section will not transmit adequate push forces and torque to theregion of the catheter distal to the bend and soft polymer.

FIG. 15C illustrates a magnified view of a portion of catheter 100 thattraverses the acute bend between the right subclavian 51 and the rightinternal carotid 53 arteries. The catheter 100 is designed such that thehybrid section 220 is positioned (or of a sufficient length) such thatthe hybrid section 220 is located within the bend when the distal end ofthe catheter 100 is at or near its intended target. FIG. 15C illustratesthe catheter 100 as having multiple material sections 134, 206, etc.However, in this variation, the hybrid section 220 includes a materialsection 210 that is stiffer and allows for torque and force transmissionof the catheter 100. The hybrid section 220 can also include one or morediscrete sections of material 208 that provide a desirable materialproperty that is different from the base material section 210. In thisexample, the discrete sections of material 208 comprise a flexiblematerial. Such a construction allows the catheter to bend acutelybecause of the flexible discrete material sections 208. Meanwhile, theharder durometer base section 210 transmits pushing forces and torque toa distal region of the catheter.

FIG. 15D shows a number of non-exhaustive design configurations toproduce a hybrid region as shown in FIGS. 15A and 15C. The hybrid regionof the catheter/finished tube is formed from a plurality of materials130 joined together where a base material 210 is interrupted by adiscrete section of a second material 208 having different propertiesthan the base. For example, in one variation of the design, materials210 can comprise a stiffer/harder durometer material or polymer whilematerials 208 comprise flexible/soft material or polymer. Clearly, anymaterial properties other than hard/soft materials can be selected andconfigured into a hybrid region.

It is noted that the polymer strands disclosed herein can extend in ahelical manner about the inner braid/coil or support structure. Inadditional variation, the polymer strands can be aligned in a lengthwisemanner with an axis of the catheter and wrapped about the supportstructure to form a catheter section. Any number of manufacturingpractices can be used to produce the catheter constructions of thepresent disclosure. For example, the strands can be directly wrapped ona liner/braid construction and then fused together to form a catheterconstruction; 2) the strands can be wrapped over a tube and fused, thentransferred to the remaining components to produce a catheterconstruction; and/or 3) the strands can be produced as a flatconstruction (either fused together, extruded, molded, or otherwiseformed) and then ribbon assembly wrapped and fused onto a liner/braid.It is understood, that any manufacturing process is within the scope ofthis disclosure and should not be limiting upon any claimed structure toany claims relating to composite polymer tubes or catheterconstructions.

As for other details of the present invention, materials andmanufacturing techniques may be employed as within the level of thosewith skill in the relevant art. The same may hold true with respect tomethod-based aspects of the invention in terms of additional acts thatare commonly or logically employed. In addition, though the inventionhas been described in reference to several examples, optionallyincorporating various features, the invention is not to be limited tothat which is described or indicated as contemplated with respect toeach variation of the invention.

Various changes may be made to the invention described and equivalents(whether recited herein or not included for the sake of some brevity)may be substituted without departing from the true spirit and scope ofthe invention. Also, any optional feature of the inventive variationsmay be set forth and claimed independently, or in combination with anyone or more of the features described herein. Accordingly, the inventioncontemplates combinations of various aspects of the embodiments orcombinations of the embodiments themselves, where possible. Reference toa singular item, includes the possibility that there are plural of thesame items present. More specifically, as used herein and in theappended claims, the singular forms “a,” “and,” “said,” and “the”include plural references unless the context clearly dictates otherwise.

It is important to note that where possible, aspects of the variousdescribed embodiments, or the embodiments themselves can be combined.Where such combinations are intended to be within the scope of thisdisclosure.

1. A catheter tubing comprising: a tubular body having a first sectionand a second section each extending along an axial length of the tubularbody; and a plurality of material sections extending spirally along theaxial length to form a wall of the tubular body, the wall a firstsection and a second section, where each material section of theplurality of material sections is sealingly joined to an adjacentmaterial section to form the wall; wherein each of the plurality ofmaterial sections comprises a structural property respectively and wherethe structural property of at least two material sections is different;wherein the first section comprises a first sequence of materialsections, and wherein the second section comprises a second sequence ofmaterial sections such that the first sequence of material sections isdifferent than the second sequence of material sections causing astructural property of the first section to be different than astructural property of the second section.